Scanning electron microscopy of dry hide working tools: The role of abrasives and humidity in microwear polish formation

This paper presents the results of the scanning electron microscopy of a series of experimental tools designed to investigate the role of abrasive agents and humidity in microwear polish formation. The tools—35 end scrapers—were divided into four groups and used to work dry hide. It was found that both humidity and abrasive agents are two basic variables in the development of the microwear polish.     

Practical quantitative lithic use-wear analysis using multiple classifiers

Although use-wear analysis of prehistoric stone tools using conventional microscopy has proven useful to archaeologists interested in tool function, critics have questioned the reliability and repeatability of the method. The research presented here shows it is possible to quantitatively discriminate between various contact materials (e.g., wood, antler) using laser scanning confocal microscopy in conjunction with conventional edge damage data. Experiments with replica and prehistoric tools suggest the quantitative method presented here provides valid functional inferences and is flexible enough to accommodate other relevant sources of data on tool function.     

Pore‐scale analysis of trapped immiscible fluid structures and fluid interfacial areas in oil‐wet and water‐wet bead packs

The objective of this study is to obtain quantitative evidence of pore‐scale immiscible fluid distribution in oil‐wet and water‐wet porous media using X‐ray computed microtomography. Temporal and spatial saturation profiles, as well as surface and interfacial areas, are thoroughly analyzed through cycles of drainage and imbibition using samples with different wetting characteristics but similar pore structures. The population of individual immiscible fluid structures (‘blobs’) was also evaluated. The specific nonwetting phase surface areas of both porous media are found to be in close correlation with the specific solid surface area. On the other hand, the differing wetting strengths of the two porous media affect the curvature of the fluid–fluid interface and thus the specific meniscus interfacial area of the two porous media. Although the magnitude of the specific meniscus interfacial areas is different, they both trend toward a maximum at wetting phase saturations of 0.35–0.55. The differences in wetting characteristics are also apparent in the blob populations. The number of blobs in the oil‐wet porous media is three times greater than that of the water‐wet porous media at similar saturations; the increase in population is a result of the increase in the amount of smaller blobs inhabiting the smaller pore spaces. The surface areas of individual blobs as a function of the individual blob volumes are found to closely agree with the specific surface area of a sphere at blob volumes below the minimum individual grain volume and with the specific pore space surface area above this volume. These results show how wettability and saturation history influence the distribution of immiscible fluids within the pore space.     

Modeling and deterioration mapping of façades in historical urban context by close-range ultra-lightweight UAVs photogrammetry

Deterioration mapping of façades may be a challenging task in historical urban contexts, often characterized by narrow streets and tall buildings. In these situations, the application of Terrestrial Laser Scanning or Terrestrial Photogrammetry does not provide satisfactory results. Furthermore, the use of Unmanned Aerial Vehicles, the so-called “drones”, is generally forbidden in crowded places for safety reasons unless they are lighter than a weight imposed by the regulations in force in each country. This article presents the application of a very small and ultra-lightweight drone (less than 300 g) equipped with a low-cost camera, particularly suitable for operating in very narrow spaces. A close range photogrammetric survey performed to analyze a huge historical building façade in Bologna (Italy) pointed out a good accuracy level, confirmed by the validation of the results carried out by a 3D laser scanner survey. Moreover, a map of the degradation has been realized to support further restoration analysis, demonstrating that this low-cost, fast, and easy-to-use survey technique can be applied to other similar urban contexts at the same time.     

Towards a Risk Management and Conservation Plan for the Djin Blocks at the World Heritage Site of Petra,Jordan: The Case of Djin Block No. 9

Cultural heritage is subjected to many pressures and risks. Over the past few years, the use of digital technologies has significantly changed the approaches to cultural heritage documentation for the purpose of condition assessment and conservation. The integration of novel approaches and techniques has permitted a detailed examination and assessment of damage, deterioration due to weathering and erosion, and their mechanisms. This study seeks to contribute to the preservation and conservation of the significant heritage of the so-called Djin Blocks at the World Heritage Site of Petra in Jordan. While these three dimensional cuboid rock-cut monuments have been subject to extensive conservation studies, this is the first time they have been subjected to 3D recording and multispectral photography, with the aim of recording damage caused by the ravages of time.

This study presents the results of the documentation of the case study Djin Block No. 9. A variety of systematic documentation techniques were used, including 3D recording with terrestrial laser scanning (TLS), close-range photogrammetry, multispectral imaging, and thermography records. In addition, pathological studies of the erosion from various causes and an analysis of the effect of weathering on Djin Block No. 9 are performed. Based on this data, the paper presents recommendations for developing risk management and conservation planning of Djin Block No. 9.     

The Role of Cross‐Scale Institutional Linkages in Common Pool Resource Management: Assessing Interstate River Compacts*

This article extends the Institutional Analysis and Development Framework's seminal research on common pool resource (CPR) management in new directions by exploring how the design principles of robust and enduring CPR management, initially proposed by Elinor Ostrom in 1990, can be used to measure and assess cross‐scale institutional linkages. This study examines data from 14 interstate river basin compacts in the western United States to identify the types of linkages established in these interstate settings, the factors that contribute to the emergence of diverse types of linkages around these shared resources, and how different types of linkages perform. Using Ostrom's CPR design principles to operationalize and measure linkages, the study shows that diverse types of cross‐scale linkages were created under the 14 interstate compacts, with linkages related to monitoring found to be particularly prevalent. The types and diversity of linkages can largely be explained by the conditions under which compacts emerged and the water management issues states jointly face. In applying the evaluative criteria operationalized by the CPR design principles, this research further shows that the monitoring and collective choice linkages created by compacts tend to be of higher quality, while enforcement and conflict resolution linkages appeared to be of the lowest quality. In addition to developing the IAD literature on CPR management, these findings offer critical insights for assessing the capacity of interstate river basin compacts in the western United States to manage shared resources successfully, as well as insights for what types of institutional investments may be needed for enhanced resource governance.     

The Santa María pottery of El Bolsón valley (Catamarca,Argentina): Compositional characterization and implications on the elaboration processes,ca. 1000–1600 ce

The results obtained from the multi-analytic compositional characterization of ceramic pastes and paints of the Santa María style, from the El Bolsón valley (Belén Department, Catamarca Province, Argentina), are presented here. This pottery style had a wide regional distribution in Northwestern Argentina between ca. 1000 and1600 ce and is characterized by its complex iconography painted in black, cream and red. The analyses show that the containers correspond to the technical tradition of using grog temper and suggest that its manufacture involved a double firing process. This reveals a new practice for the time.